Postdoctoral Research Associate, Washington University in St.Louis
Each year about 3-4% of babies are born with some type of birth defect and due to these congenital defects an estimated 303000 newborns die within a month of birth every year worldwide (WHO). The ones that survive can suffer from long-term disability or require invasive treatment, impacting the individual, their families, and health-care system. Most congenital defects are caused by genetic or environmental factors or a combination of both, however in most cases the cause remains unknown. This multifactorial nature makes it more difficult to pinpoint the cause and hence finding a therapeutic target. Perinatal infections account for 2-3% of all congenital anomalies. Infections known to produce congenital defects have been described as TORCH, which includes Toxoplasmosis, Others, Rubella, Cytomegalovirus, and Herpes. Our research if focused on looking at effects virus infection during pregnancy can cause to the developing fetus. Many intrauterine viral infections during pregnancy are associated with abortion, congenital anomalies, fetal death, and perinatal infection. However, the mechanism of viral pathogenesis that is by which the virus attack the cells and changes the cellular functioning remain unanswered. Although the major cause of congenital anomalies when a baby is born with organ defects can be attributed to the genetics, there have been reports that environment also plays an important role in it. Genetic predisposition of an individual can interact with the environment and cause the defect. This environmental variability can be related to infections during pregnancy in genetically susceptible individuals. Our studies could significantly influence the future understanding (and potential management through public health measures) of congenital defects as well as introduce a new avenue of research for congenital defects not previously investigated.
Abstract: TORCH infections classically comprise toxoplasmosis, Treponema pallidum, rubella, cytomegalovirus, herpesvirus, hepatitis viruses, human immunodeficiency virus, and other infections, such as varicella, parvovirus B19, and enteroviruses. The epidemiology of these infections varies; in low-income and middle-income countries, TORCH infections are major contributors to prenatal, perinatal, and postnatal morbidity and mortality. Evidence of infection may be seen at birth, in infancy, or years later. For many of these pathogens, treatment or prevention strategies are available. Early recognition, including prenatal screening, is key. This article covers toxoplasmosis, parvovirus B19, syphilis, rubella, hepatitis B virus, hepatitis C virus, and human immunodeficiency virus.
Pub.: 14 Feb '15, Pinned: 27 Jun '17
Abstract: Women may be infected during pregnancy with infectious agents that are often passed unnoticed; however, the causative agent may still traverse the placenta and infect the developing embryo and fetus. Several of these agents (i.e. rubella, cytomegalovirus or Toxoplasma Gondii) may cause severe fetal damage, but most other infections in pregnancy seem to be much less dangerous to the fetus. In this review we discuss the effects of several viral infections during pregnancy where the effects on the developing embryo and fetus are infrequent, but they may sometimes cause severe neonatal disease. The following viruses are discussed: coxsackie and echoviruses, measles and mumps, polioviruses, Japanese and Venezuelan equine encephalitis viruses, West Nile virus and hepatitis viruses A, B, C, D and E. Coxsackie B virus may cause an increase in early spontaneous abortions and rarely, fetal myocarditis; echoviruses do not seem to damage the fetus; measles and mumps may cause increased early and late fetal death and neonatal measles or mumps. The viruses affecting the nervous system may increase early and late spontaneous abortions and, rarely, cause severe damage to the fetal brain. Hepatitis B virus has a high rate of vertical transmission causing fetal and neonatal hepatitis. Hepatitis A, C and E are rarely transmitted trans-placentally; if transmitted, they may cause hepatitis. There is no evidence that immunization in pregnancy against these diseases (with attenuated viruses) may adversely affect pregnancy outcome.
Pub.: 17 Feb '06, Pinned: 27 Jun '17
Abstract: Despite the prevalence of viral infections in the American population, we still have a limited understanding of how they affect pregnancy and fetal development. Viruses can gain access to the decidua and placenta by ascending from the lower reproductive tract or via hematogenous transmission. Viral tropism for the decidua and placenta is then dependent on viral entry receptor expression in these tissues as well as on the maternal immune response to the virus. These factors vary by cell type and gestational age and can be affected by changes to the in utero environment and maternal immunity. Some viruses can directly infect the fetus at specific times during gestation, while some only infect the placenta. Both scenarios can result in severe birth defects or pregnancy loss. Systemic maternal viral infections can also affect the pregnancy, and these can be especially dangerous, because pregnant women suffer higher virus-associated morbidity and mortality than do nonpregnant counterparts. In this Review, we discuss the potential contributions of maternal, placental, and fetal viral infection to pregnancy outcome, fetal development, and maternal well-being.
Pub.: 02 May '17, Pinned: 27 Jun '17
Abstract: Viral infections during pregnancy have long been considered benign conditions with a few notable exceptions, such as herpes virus. The recent Ebola outbreak and other viral epidemics and pandemics show how pregnant women suffer worse outcomes (such as preterm labor and adverse fetal outcomes) than the general population and non-pregnant women. New knowledge about the ways the maternal-fetal interface and placenta interact with the maternal immune system may explain these findings. Once thought to be 'immunosuppressed', the pregnant woman actually undergoes an immunological transformation, where the immune system is necessary to promote and support the pregnancy and growing fetus. When this protection is breached, as in a viral infection, this security is weakened and infection with other microorganisms can then propagate and lead to outcomes, such as preterm labor. In this manuscript, we review the major viral infections relevant to pregnancy and offer potential mechanisms for the associated adverse pregnancy outcomes.
Pub.: 15 Jan '15, Pinned: 27 Jun '17